X-ray on single crystal superalloy SRR99 : Mismatch gamma/gamma' : Mosaicity and internal stress
The aim of this work is to set up an X-ray diffraction technique able to study in detail the gamma-gamma' lattice mismatch and the anisotropy of both phases as a function of location in thermo-mechanical fatigued specimens. A four axis diffractometer with a copper source is used. X-ray profiles are recorded on SRR99 single crystal coated with a NiAl layer. Two measurements (into the bulk and close to the coating) are performed on two different samples before and after thermo-mechanical fatigue testing. Rocking curve acquisitions are achieved by integration of the individual (theta, 2 theta)-scan at different rocking angle (omega), while the evolution of intensity as a function of tilting angle (Chi(c)) is recorded in order to obtain information about the range of orientation of crystallites. A numerical separation of the two strongly overlapping gamma and gamma' peaks, which is carried out by means of the PROFIL software developed for this purpose, discloses information related to both phases.
Bibliographic Reference: Article: Acta Metallurgica et Materiali
Record Number: 199510941 / Last updated on: 1995-08-10
Original language: en
Available languages: en